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The following are citations selected by title and abstract as being related to Computer-Human Interaction, resulting from a computer search, using Dialog Information Services, of the Dissertation Abstracts Online database produced by University Microfilms International (UMI).

The following are citations selected by title and abstract as
being related to Computer-Human Interaction, resulting from a computer
search, using Dialog Information Services, of the Dissertation
Abstracts Online database produced by University Microfilms
International (UMI). Included are UMI order number, title, author,
degree, year, institution; number of pages, Dissertation Abstracts
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Today's second language teaching/learning practice has been
criticized for lacking adequate means to equip students with effective
methods for reading second language texts. This problem is further
compounded by the fact that the current development of software for
second language learning fails to address this problem and, instead,
inadvertently reinforces the use of inefficient reading strategies. The
objective of this thesis is (a) to demonstrate that an adequate theory
basis exists in the fields of psychology and pedagogy of reading for
designing a software program which addresses the teaching/learning
problem; (b) to generate the design of a second language reading
program that corresponds to the theory and document the programming
components of a first prototype version of the tool software; (c) to
present the methodology and results of an initial formative evaluation
demonstrating that the design meets criteria for utilization in the
light of the teaching/learning problem being addressed; and (d) to
discuss the implications of the design and the prototype software
program in the light of relevant theory. With respect to the
operational characteristics, the results of the formative evaluation
showed that the prototype tool software met the basic criteria for
functional utilization and appeared robust and posed no obstacle to use
for further experimentation and research. With respect to promoting
behaviours related to the Expert L2 reading, the data suggests that
tool use promoted greater processing in the target language. Pending
further research, initial results suggest that tool users were more
willing and able to generate the recall meaning of words encountered in
the text. The thesis concludes by specifying a number of areas for
further research with the tool.

Douglas, Jane Yellowlees; New York University Ph.D. 1992, 250 pages; University Microfilms Order Number ADG92-37749.

This dissertation examines the ways in which hypertext affects the
act of reading. In the new and, as yet, convention-less environment of
hypertext space, it is possible to perceive aspects of the transaction
between reader and text normally not visible amid the familiar
trappings of print environments, enabling us to answer the questions:
how do readers make meaning. How do readers negotiate the "blanks" or
"gaps" in the text which nearly all theorists claim are endemic to the
act of reading. Are endings essential to the process of reading. Do
hypertext readers have more autonomy than readers of print narratives.
How will the use of hypertext in education affect the definition of
learning.

After exploring the ways in which hypertext narratives resemble
and differ from traditional and avant garde print narratives, the
dissertation examines the strategies of readers attempting to piece
together a short story cut into segments and how our perceptual
inclination toward seeing connections in the world around us enables us
to see multiple connections between elements in a text. The study goes
on to examine the meaning making process of two sets of readersone
reading a print short story and one an interactive version based on the
print storyand the ways in which the readers' respective processes of
coming to understand the text reflect their tendency to arrive at
interpretive decisions based upon their perception of the relationship
between the significance and "place" of textual nodes in hypertext's
virtual, three-dimensional space.

Finally, an exploration of the strategies which readers use
when confronting texts which have no physical "ending" uncovers the
link between the act of prediction as one of the chief constituents of
the process of meaning making and our need to anticipate endingseven
when the sort of determinate, physical closure inherent in print
narratives is deferred or displaced. At the same time, the network of
connections and nodes which forms the hypertext can oblige readers to
participate in something resembling a game between reader, text, and
unseen author, where readers must anticipate authorial intention in
order to navigate through the author's "intentional network".

Nord, Robert Louis; Carnegie-Mellon University Ph.D. 1992, 174 pages. University Microfilms Order Number ADG92-38823.

A formal method for systematically integrating general-purpose
software modules into efficient systems is presented. The integration
is accomplished through adjustment of abstract interfaces and
transformation of the underlying data representations. The method
provides the software designer with the ability to delay or revise
design decisions in cases where it is difficult to reach an a priori
agreement on interfaces and/or data representations.

To demonstrate the method, the development of a text buffer for
a simple interactive text editor is given. For each basic operation on
the text buffer, a natural and efficient choice of data representation
is made. This organizes the operations into several "components," with
each component containing those operations using the same data
representation. The components are then combined using formal
program-manipulation methods to obtain an efficient composite
representation that supports all of the operations.

This approach provides meaningful support for later adaptation.
Should a new editing operation be added at a later time, the initial
components can be reused in another combining process, thereby
obtaining a new composite representation that works for all of the
operations including the new one. There are also ramifications for the
application of formal methods to larger-scale systems, as this method
can be applied to the manipulation of the interfaces between modules in
larger software systems.

Hammontree, Monty Lee; Old Dominion University Ph.D. 1991, 228 pages; University Microfilms Order Number ADG92-30320.

The present study was conducted in two phases to determine design
tradeoffs relating to command bar menu and bypass code-based techniques
for interacting with computers. Forty eight subjects participated. In
the first phase of the experiment, mouse-, chorded key-, and function
key-based menu selection techniques were compared. It was found that
menus were accessed much faster with spatially mapped function keys as
compared to chorded key sequences or mouse inputs, and that relative to
mouse inputs compatible letter keys lead to faster command selection
times. Further, the function key-based technique yielded the fastest
combined access and selection times, the fastest block completion
times, and the fewest errors. In the second phase of the experiment,
four experimental conditions were produced by crossing two menu input
devices (i.e., mouse and keyboard) with two bypass coding structures
(i.e., function key-based codes and chorded key-based codes). It was
found that the groups which used function key-based codes entered the
menu designating portion of the bypass codes faster than those that
used chorded key-based codes. The coding structure based on spatially
mapped function keys also yielded faster task completion times.
Furthermore, there were fewer command substitution errors with this
coding structure. Comparisons between the groups with no prior exposure
to the code sequences (i.e., the groups that used the mouse to make
menu selections during the first phase) revealed that the function
key-based technique also led to fewer command omissions and fewer
extraneous command selections. Finally, subjective data showed menus
were felt to be easier to learn, less demanding in terms of mental
resources, and less anxiety provoking than bypass codes. In contrast,
bypass codes were felt to be more natural, more convenient to use, and
faster in terms of task times and better in terms of task performance.
The findings of this study clearly indicate that both menu- and bypass
code-based styles of control should be provided to promote user
acceptance. Furthermore, the performance advantages observed for the
function key-based technique point to it as the menu selection and
bypass technique of choice.

Durrani, Qaiser Shehryar; The George Washington University D.Sc. 1992, 253 pages; University Microfilms Order Number ADG92-38110.

Experts sometimes make errors due to biases in their judgement. This
research was conducted to find out if the decision making process of
experts can be improved by critiquing their performance employing user
modeling techniques. The user modeling concept focuses on providing
help to users based on individual user capabilities. The goal is to see
how a computer critic, through user modeling, can improve an expert's
performance in bias situations.

Psychological testing techniques are finding increasing use in
various disciplines, such as psychopathology, personal attributes,
socialization factors, memory studies, school achievement tests, etc.,
to achieve better results. In this research, several standard
psychological testing techniques are utilized to implicitly assess
users' cognitive abilities and to build user profiles. Use of cognitive
testing is in contrast to existing user models that use explicit query
based techniques to build user profiles.

Two empirical studies were conducted to determine the effects
of the user modeling on expert decision making during task performance.
The first study proposed to find a relationship between cognitive
abilities and human biases. Three standard psychological tests were
administered to a control group to capture user cognitive abilities.
The same user group was then given a set of eight tasks to perform.
These tasks were designed to measure three of the most common biases
that experts exhibit. A matrix of cognitive abilities and human biases
was developed based on the task outcomes. The matrix was built using
multivariate statistical analysis techniques such as, factor analysis,
correlational analysis, stepwise multiple linear regression, and
discriminant analysis. Cognitive profile rules were then extracted from
this matrix so it could be implemented in the user model.

The second study verified the user model which in turn
validated the cognitive profile rules. Here a new group of subjects
took the same tests. The psychological tests captured the cognitive
abilities of the subjects. Based on these cognitive measures and the
matrix developed in the first study, a user model was built for each
subject. During the repetition of the eight tasks, the user model
predicted the likelihood of biases being committed and triggered
different critiquing screens to assist the subjects in overcoming their
biases. As the tasks progressed, the deviations from the matrix's
predictions prompted the user model to update itself.

Hesketh, Richard Laurence; University of Kent at Canterbury (United Kingdom) Ph.D. 1992, 243 pages; University Microfilms Order Number ADGDX-97627.

Available from UMI in association with The British Library.

Modern graphical user interfaces have opened up the use of
computers to an ever increasing range of users. Creating interfaces
suited to the different range of user skills has proved to be
difficult. Many software tools have been created to aid designers in
the production of these interfaces. However, designers still cannot
produce interfaces and applications that are suitable for all
end-users. Compared with designers, users have a better understanding
of the tasks they wish to complete. It is therefore vital that
end-users are involved in the development of interfaces and
applications. One such involvement is through the tailoring of
interfaces by the end-users themselves. A system is tailorable if it
allows end-users to modify its appearance and/or functionality. Through
these modifications end-users can produce interfaces and applications
more suited to their requirements. In this thesis we examine tailorable
systems for graphical workstations. We define a model of tailoring and
investigate existing systems. From this investigation an example
framework for inherently tailorable applications has been advised. To
test the ideas presented a number of software products have been
designed and implemented. These products have been designed to ease the
difficulty found by both application developers, who wish to create
tailorable systems, and by end-users who wish to take advantage of
them. The conclusion is drawn that, through the careful design of
underlying mechanisms, tailorable systems can be created efficiently by
designers.

Weiss, William Samson; The University of Connecticut Ph.D. 1992, 384 pages; University Microfilms Order Number ADG93-00959.

This project involves the development of a technique for modeling
and analytically evaluating human-computer interfaces. The modeling
technique is supported by an extensive set of theorems and algorithms
which describe the various model building phases. The theorems and
algorithms show that the representations of each human-computer
interface converges to a single probabilistic finite state model which
accurately represents the human-computer interaction. The resulting
probabilistic finite state models are then used as predictors to
generate data which can be statistically analyzed to yield a comparison
between alternative human-computer interfaces.

The technique uses an approach in which probabilistic finite
state models of the prospective human-computer interfaces are
constructed. Specifications of the human-computer interfaces provide
for the partial definitions of initial probabilistic finite state
models. Initially, the missing components of the probabilistic finite
state models are the time distributions which specify how much time is
spent in each state and the probabilities associated with the state
transitions. Experiments are required to determine the time
distributions and state transition probabilities. For this project a
set of experiments was performed using simulated human-computer
interfaces to a CASE system component which calculates time performance
of software for parallel architectures. The data collected during the
experiments were used to complete and refine the probabilistic finite
state models. The refined models were then exercised as predictors and
the generated data was statistically analyzed to compare the
interfaces. The results demonstrated that the modeling and evaluation
technique can be used effectively in the design and refinement of
human-computer interfaces.

Bailey, Margaret Lynn; Kansas State University Ph.D. 1992, 117 pages; University Microfilms Order Number ADG92-29230.

This study compared the effects of three variations in interactivity
in an interactive video lesson on achievement of lesson concepts,
attitudes regarding the learning activity, and frequency and type of
peer interaction among undergraduate physics students.

Interactivity was defined as the level of opportunity for
interaction between the user and the interactive video program. Three
variations of the same software program were created with the following
programmed variations in level of interactivity: No Interactivity (no
opportunities for interaction), Low Interactivity (opportunities for
interaction limited to control of pace, embedded questions, feedback
and remediation on an incorrect response) and High Interactivity
(increased opportunities for interaction including control of sequence,
pace, videodisc controls, number of rope experiments, embedded
questions, feedback and choice for remediation).

Subjects (N = 52) were volunteers from an undergraduate course
in physics. Subjects were matched with a peer and the pairs were
randomly assigned to one of three treatment groups. Subjects were
audiotaped for transcription of verbal interaction behavior. After
completing the interactive video lesson, subjects independently
completed a criterion-referenced posttest and attitude scale.

Group means for recall and transfer posttest scores, attitude
scores, overall frequency of verbal interaction and frequency of
specific types of verbal interaction (task-related, procedure-related,
socio-emotional and off task) were tested for significance with a
one-way analysis of variance. The analyses revealed no significant
difference between groups on overall posttest scores. The High
Interactivity group, however, scored significantly lower on the recall
portion of the posttest than did the No and Low Interactivity groups.
In addition, the analyses revealed significantly lower attitude scores
for the No Interactivity group when compared to the Low and High
Interactivity groups.

Analyses regarding peer interaction behavior revealed that the
No interactivity group had significantly less frequent peer
interactions than the Low and High interactivity groups. Further, the
No interactivity group had significantly less frequent task-related and
socio-emotional peer interaction than the Low and High interactivity
groups. The High interactivity group had significantly more frequent
procedure-related interaction than did the No or Low groups. Finally,
groups did not significantly differ in the frequency of off task
interaction.

Beginning in the mid-1980s, there has been a move toward using
computers in writing classrooms at all levels. While the reviews of
their effectiveness are mixed, computers continue to play a larger role
in the teaching of composition as time goes on, possibly because today,
and in the foreseeable future, computers are the way we write at work.

Traditionally, students have been excluded from literacy, and
hence, empowerment, because of economics and social class. But today,
with the predominance of computerized writing, both in the classroom
and at work, we are finding a new exclusionary factor is
surfacingcomputer anxiety.

This study, structured in two phases, looks at computer anxiety
in the composition classroom in an effort to find ways to deal with the
problem so students can succeed at computerized writing. Phase one
consisted of a multiple case study of two computer anxious students and
preliminary quantitative studies of six other computer anxious
students. Phase two examined 185 subjects with respect to prior
experience and eight computer anxious subjects on various personality
traits.

Findings show that computer anxiety is strongly correlated not
with experience, but rather with the pleasantness or unpleasantness of
prior experience (r =.75954). Subjects in the study who had no previous
experience with computers also were without anxiety. Further, computer
anxiety may actually be programming anxiety in disguise. Students who
were computer anxious often talked about bad programming experiences as
the genesis of their problem.

Students who did prior planning, and were adventuresome and/or
self-reliant had a better chance of overcoming computer anxiety than
did their less adventuresome and self-reliant counterparts.

Task avoidance, composing with pen and paper, and editing on
screen may all predispose the computer anxious student to failure in
overcoming the problem.

The results of this study suggest that instructors in
computerized composition classes should identify computer anxious
students when possible, strongly discourage absences, especially early
in the course, pay special attention to keeping the students on-task as
much as possible, and encourage them to write on line, but edit on hard
copy.

Hsieh, Feng-Jui; Purdue University Ph.D. 1992, 269 pages; University Microfilms Order Number ADG93-01313.

This study investigated the instructional effectiveness and
motivational appeal of animation and manipulation on adults' learning
of mathematical concepts in a computer-based lesson.

The subjects were 54 college students who participated in two
CBL sections as part of their mathematics class. They were randomly
assigned to receive instruction with either animation or no animation,
as well as manipulation or no manipulation. The computer based lesson
was developed by the researcher and introduced the concept of Venn
diagrams.

Achievement was measured immediately after the two CBI lessons
by both paper-and-pencil tests and tests on the computer. One week
later, a paper-and-pencil test was distributed to evaluate students'
retention. Continuing motivation was assessed through a questionnaire.

Findings included: (1) Animation enhanced adults' retention
when the learning tasks required high level cognitive processes such as
analysis or synthesis; (2) Animation did not help adults' learning or
retention when the learning tasks required mainly the comprehension of
mathematical concepts; (3) Animation increased continuing motivation;
(4) Manipulation helped the transference of mathematical concepts
learned through a computer to paper-and-pencil tests; (5) Manipulation
did not promote intrinsic motivation. Recommendations for further
studies were also provided in this study.

Scott, Derek; University of Durham (United Kingdom) Ph.D. 1991, 380 pages; University Microfilms Order Number ADGD-97867.

Available from UMI in association with The British Library. Requires signed TDF.

This wide-ranging study explored various parameters of visual
search in relation to computer screen displays. Its ultimate goal was
to help identify factors which could result in improvements in
commercially available displays within the `real world'. Those
improvements are generally reflected in suggestions for enhancing
efficiency of locatability of information through an acknowledgment of
the visual and cognitive factors involved.

The thesis commenced by introducing an ergonomics approach to
the presentation of information on VDUs. Memory load and attention were
discussed. In the second chapter, literature on general and theoretical
aspects of visual search (with particular regard for VDUs) was
reviewed.

As an experimental starting point, three studies were conducted
involving locating a target within arrays of varying configurations. A
model concerning visual lobes was proposed.

Two text-editing studies were then detailed showing superior
user performances where conspicuity and the potential for peripheral
vision are enhanced. Relevant eye movement data was combined with a
keystroke analysis derived from an automated protocol analyser.

Results of a further search task showed icons to be more
quickly located within an array than textual material. Precise scan
paths were then recorded and analyses suggested greater systematicity
of search strategies for complex items.

This led on to a relatively `pure' search study involving
materials of varying spatial frequencies. Results were discussed in
terms of verbal material generally being of higher spatial frequencies
and how the ease of resolution and greater cues available in peripheral
vision can result in items being accessed more directly.

In the final (relatively applied) study, differences in eye movement indices were found across various fonts used.

One main conclusion was that eye movement monitoring was a
valuable technique within the visual search/VDU research area in
illuminating precise details of performance which otherwise, at best,
could only be inferred.

Hou, Tung-Hsu (Tony); State University of New York at Buffalo Ph.D. 1992, 233 pages; University Microfilms Order Number ADG93-01855.

Objectives of this research are to compare hybrid systems to human
inspection and automated inspection systems, to demonstrate the
feasibility of the hybrid inspection systems, and to develop a
framework to allocate humans and computers in an inspection system for
various conditions.

Based on a search-decision model of inspection (Drury, 1978),
two hybrid human-computer inspection systems were developed. Their
performance of inspecting surface mount device images was compared to
human inspection and two automated inspection systems. Missing
components, wrong-sized components, and misaligned components were used
as the three fault types in this investigation. Experimental results
showed that both hybrid systems were better in inspection accuracy than
the two automated inspection systems, and one hybrid system had better
performance than human inspection. The feasibility of using both humans
and computers in inspection has been clearly demonstrated.

The research also indicated that humans were not significantly
affected by contrast while the performance of the systems involving
computers deteriorated with decreased contrast levels. It was also
shown that humans were better at detecting missing components and
wrong-sized components while computers were better at detecting
misaligned components.

Based on the above findings, a procedure was proposed for the
allocation of inspection functions for different conditions. A neural
net model were applied to learn the relationships between the
conditions and performance of each alternative inspection system. The
neural net was superior in predicting the right system design to a
random selection process. The results have shown the feasibility of the
framework in allocating humans and computers in an inspection system.

Computer applications with graphical user interfaces are difficult
to build because application programmers must deal with many low-level
details. One promising solution to this problem is an object-oriented
toolkit, which offers predefined components that serve particular user
interface needs. However, the components that most toolkits provide are
complex and costly in their use of computer resources. User interface
programmers cannot use these components for many kinds of applications
because the resulting implementation would be awkward and inefficient.

This dissertation describes a new way of building user
interfaces from small, simple components that programmers can use in
large numbers to define the appearance of application views. Foremost
among these components is a lightweight graphical component called a
glyph. By using glyphs and other predefined components, programmers can
assemble powerful applications with substantially less effort than with
other techniques.

To show that the components are simple and effective, I built a
prototype toolkit, named InnerViews, and used it to implement a
document editor that uses a glyph for each character in the document.
The editor's performance is comparable to that of similar editors built
with current tools, but its implementation is much simpler. I used the
editor to prepare and publish this dissertation.

The success of InnerViews in the text and graphics domains
suggests that similar implementation benefits might be seen in building
applications that support other media such as sound, video, and
animation. Many of the techniques that make glyphs practical should
also be valuable in designing and implementing lightweight components
for these new domains.

Gupta, Aloke; University of Illinois at Urbana-Champaign Ph.D. 1993, 119 pages; University Microfilms Order Number ADG93-29049.

Graphical interfaces and windowing systems are now the norm for
computer-human interaction. Also, advances in computer networking have
given computer users access to immense distributed resources accessible
from anywhere on the network. In this setting, the desktop, or personal
computer plays the role of a user-interface engine that mediates access
to the available resources. Interface paradigms, such as the "desktop
metaphor" and "direct manipulation," provide the user with a
consistent, intuitive view of the resources. Traditional computer
research has focused on enhancing computer performance from the
numerical processing and transaction processing perspectives. In the
research described in this thesis a systematic framework is developed
for analyzing and improving the performance of window systems and
graphical user interfaces. At the system level a protocol-level
profiling strategy has been developed to profile the performance of
display-server computers. A sample protocol-level profiler, Xprof, has
been developed for applications under the X Window System. At the
microarchitecture level the memory access characteristics of windowing
programs are studied. Cache tradeoffs for a frame-buffer cache are
presented. A cache organization is proposed to improve the frame-buffer
performance.

Sears, Andrew Lee; University of Maryland College Park Ph.D. 1993, 217 pages; University Microfilms Order Number ADG93-27491.

Layout Appropriateness is a design philosophy that can result in
interfaces that are not only faster, but are preferred by users. Layout
Appropriateness refers to the concept of designing an interface that is
in harmony with the users' tasks. Using descriptions of the sequences
of actions users perform and how frequently each sequence is applied,
interfaces can be organized to be more efficient for the users' tasks.

Simple task descriptions have proven to be useful for both
designing new interface widgets and organizing widgets within an
interface. The benefits of simple task descriptions were demonstrated
in two applications. First, simple task descriptions were used to help
designers develop more efficient interfaces. Once designers select the
widgets necessary for an interface they must decide how to organize
these widgets on each individual screen. To aid in this process a
task-sensitive metric, Layout Appropriateness (LA), was developed.
Given the widgets to be used and the simple task description, designers
can use LA to evaluate the appropriateness of an interface layout. The
effectiveness of LA for predicting user performance and preferences was
tested in a controlled experiment with eighteen subjects. As predicted,
interfaces with better LA values were reliably faster than interfaces
with poorer LA values. In addition, interfaces with better LA values
were preferred by users.

Second, simple task descriptions were applied to the task of
organizing items within a pull-down menu. Considering the benefits of
both traditional (alphabetical, numerical, etc.) and frequency-ordered
menus led to the creation of a more efficient organization called split
menus. In split menus three to five frequently selected items are moved
to the top of the menu. Field studies at the NASA Goddard Space Flight
Center and the University of Maryland demonstrated the potential of
split menus. Selection times were reduced by between 17 and 47%, and
90% of the users preferred the split menus. A controlled experiment
with thirty-six subjects was conducted to evaluate the efficacy of
split menus. A theoretical model accurately predicted when split menus
would be faster than alphabetic menus. Split menus were also preferred
over both alphabetical and frequency-ordered menus.

Liebscher, Peter; University of Maryland College Park Ph.D. 1993, 267 pages; University Microfilms Order Number ADG93-27456.

This study focussed on the interaction between users, the system,
and tasks during information retrieval in a full-text hypertext system.
It drew on mental model theory to examine the users' views of
information retrieval systems and how these views affected their
information-seeking behavior in a hypertext system offering multiple
access methods. The access methods provided for this study were an
alphabetical index, an hierarchical subject index, Boolean string
search, and a network browser. Eleven undergraduate participants and
one expert in hypertext systems were given a number of tasks and were
observed intensively and individually over five sessions, each lasting
approximately 2 to 2.5 hours. Access methods were used individually for
the first four sessions. For the final session, all four access methods
were available. Participants were given a total of 22 information
retrieval tasks. Because the study was exploratory, no hypothesis
testing was done. Eleven research questions served to guide the design
of the protocols and the observations themselves. Results indicate that
undergraduate users of new hypertext information systems use elements
of existing mental models for information systems as they interact with
the new system. Benefits are quick learnability of system syntax and
the ability to apply known information-seeking strategies in the new
environment. Drawbacks are inefficient or failed searches due to
misapplication of mental models for familiar systems. String search
proved to be the overwhelming choice of access method for hands-on
retrieval tasks. Selection of string search was independent of task.
Principal reasons for selection of string search were a desire to do
word, rather than conceptual searches and to minimize the amount of
text scanned/read. Hypertext features, such as text embedded
highlighted links, were also used to minimize reading. User
characteristics, such as subject knowledge, computer experience, and
gender, rather than task characteristics, were factors in selection of
access method. Overall, participants were successful in their retrieval
tasks, but more successful using string search and the network browser
than using the indexes. However, success was often attained through
serendipitous browsing which indicates that the relatively small size
of the database was also a factor.